When you run experiments, there's inherently an element of the unknown. After all, we're trying to figure out things we don't know. And sometimes, things go wrong. FATALLY WRONG! Here are some of the most interesting, most intriguing, and sometimes most horrific, experimental deaths we've ever heard of.

15. Those magnificent men and their flying machines

The first post on this list is dedicated to all those brave souls who lost their lives attempting to defeat mankind's oldest enemy: gravity. Truly, there is no greater statement of belief in your own invention than hurling yourself from a high point, depending only on it for survival. Ismail ibn Hammad al-Jawhari, who tried to make wooden wings; Otto Lilienthal and his hang gliders; Franz Reichelt, a tailor who attempted to make the world's first parachute. We salute you. You attempted to beat gravity, and instead plummeted to a grisly death. Rechelt deserves special mention for not only hurling himself off the Eiffel Tower with only a poorly constructed edifice of cloth stuck to his back, but doing so during the dawn of cinematography, thus ensure the entire event was recorded for the world to remember.

14. Marie Curie

There's a certain romanticism attached to the tale of Curie. She discovered the theory of radioactivity, discovered polonium and radium, undertook the first studies of how to use these strange new theories to treat cancer, and was awarded Nobel prizes in Physics and Chemistry. However, a lifetime of exposure to the radiation, along with the universal lack of knowledge about its effects, lead to her death from aplastic anemia. She worked under such heavy radioactivity that all her notes—even her cookbook—are stored in lead lined boxes, and anyone wishing to study them has to wear protective clothing.

13. Jesse William Lazear

The Yellow Fever was a disease that most likely originated in Africa, but during the 18th and 19th century was convincingly kicking the ass of the United States. It wasn't until the 1900s that Lazear—a researcher of the "American Plague", and bearer of a name that sounds like Lazer— confirmed that it was even transmitted by mosquito. He was a tireless researcher to try and defeat the illness, to the point where he secretly exposed himself to infected mosquitos. I bet you know what happened then. Yup, he contracted the disease, and died. You want to know how Yellow Fever will do you in? Most people will just get fever, headache, chills, back pain, loss of appetite, nausea and vomiting, and then walk away with life-long immunity. The second phase, however, is the deadly one. Liver damage, jaundice, abdominal pain, bleeding from the mouth, eyes and ass. And finally, blood filled vomit. What a way to go.

12. MKULTRA

MKULTRA sounds like the stuff of conspiracy theorist's dreams. It also sounds like a badass metal band, but that's besides the point. If someone told you that the CIA was secretly testing American citizens with psychoactive drugs in order to test their effectiveness for interrogation, you'd probably give that person a nice sheet of tinfoil from which they could fashion a handsome and fetching hat. But it happened. The CIA went around dosing the fuck out of everyone, to see how LSD and other drugs functioned, and they tried to figure out mind control. Didn't really work. Hell, they even got a group of prostitutes to secretly drug up their johns to see how the acid worked on unwilling participants. Two people died from the tests: Harold Blauer, a New York professional tennis player, who was injected with a mescaline derivative called MDA during treatment for depression. This was done without his knowledge or consent, and he died after a massive overdose of the drug. Frank Olson was an Army biochemist, who was exposed to LSD under dodgy circumstances. Some say he was murdered for threatening to go public. The official version is he was given the drug, not knowing what it really was, and then jumped from 13th story window.

11. Stateville Penitentiary Malaria Study

Man, the Army sure does show up a lot on this list, huh? I guess they just have a thing for human experimentation. So, you have a prison in Illinois 1940s, and a medical department, Army and State Department who want to run a controlled study of malaria—a.k.a the disease that has killed the most human beings, ever. Oddly enough, they even got the prisoner's consent, including infamous murderer Nathan Leopold. 441 inmates volunteered, I assume for extra cigarettes or something similar, and were bitten by 10 disease carrying mosquitos each. Only one died, from a heart attack after battling a number of rounds with the fever. The interesting thing about this situation, is the defence team of the Nazis during the Nuremberg Medical Trials claimed there was no difference between the prison experiments, and the forced experimentation in the concentration camp. It was during this trial that the concept of "informed consent" was cemented, into the form we know and love today.

10. British Nuclear Tests

In the 1950s, Britain was desperate to have its own nukes, and undertook a number of atomic tests in a picturesque corner of the Pacific known as Christmas Island. Dubbed Operation Grapple, they detonated a series of atmospheric nuclear devices, without bothering to evacuate either their personnel, or the inhabitants of the island. Some reports say that instead of protective gear, the servicemen were just told to turn their backs from the explosion, and cover their faces with their hands. The men reported a flash so bright they could see their bones through their hands, and so strong that it knocked many over. And afterwards, they all ate fish from ocean, swam in the lagoon, and drank the local water. The American Government continued to perform tests in the area for years. Both sides deny any long term ill effects to the servicemen or local population.

9. The German Ebola Accident

If you've ever been in a science lab, you'll have probably run into various stringent rules about behavoir, like: no drinks, no open-toed shoes, keep experiments separate, no sex on the lab tables, etc. And you probably ignored most of them. Well a worker at an Ebola research lab in Germany knows the importance of these procedures, after she accidentally pricked herself with a needle through three layers of protective gloves. She was instantly quarantined and given an experimental treatment, and managed to survive. So yes, she lived, and doesn't really belong on this list. But, it gives me a chance to talk about Ebola, so fuck you all, I'm running with it. Ebola is nasty. Like really nasty. It has a mortality rate of 50%-89%, depending on strain. So, if you get the nicest, sweetest, most cuddly version of it, it's still even odds of you kicking the bucked. The nastier ones will almost certainly do you in. And you know how you go? You bleed and shit yourself to death, while all your organs shut down. Awesome.

8. The Fallout Experiments

Oh fallout, white and fluffy as snow, it descends from the heavens after a nuclear explosion. It's radioactive dust that's created when a nuclear bomb goes off, and its incredibly toxic, and has a tendency to work its way into the food chain. It leads to cancer, death, and horribly mutated babies How do we know this? Because the American Government exposed the inhabitants of Rongelap Atoll to it. Yeah, it would have sucked to live on a Pacific Island in the 50s and 60s, when all this shit was being blown up. This one wasn't intentional, but they sure didn't mind watching the effects. It was after they detonated a lithium deuteride bomb, which ended up producing a much larger explosion than originally planned, combined with strong winds that bore the dust over the islands. They called the severely malformed offspring of the island's inhabitants "jellyfish babies". Nice.

7. Dr. Henry Cotton

Dr Henry Cotton. Sounds like a nice and fluffy guy, doesn't he? Well, he wasn't. He ran the New Jersey State Hospital at Trenton (previously called New Jersey State Lunatic Asylum, now known as Trenton Psychiatric Hospital), and thought that you could cure insanity via removing parts of your patients. That's right, he beliveved rudely ripping organs from your body would cure delusions. He'd start with removing all the teeth, move on to the tonsils and sinuses, and then, in no particular order, the testicles, ovaries, gall bladders, stomachs, spleens, cervixes, and colons. Wow, with all that gone, you'd be down to almost no internal organs. One example was "An 18 year-old girl with agitated depression [who] successively had her upper and lower molars extracted, a tonsillectomy, sinus drainage, treatment for an infected cervix, removal of intestinal adhesions -- all without effecting improvement in her psychiatric condition. Then the remainder of her teeth were removed and she was sent home, pronounced cured".

Seeing as this was the 1920s, and before antibiotics, I'm sure you can imagine what the survival rate was like. Cotton claimed an 85% success rate, which was completely wrong. It also turns out that the mortality rate among his patients was around 45%. Even if you did survive, you'd be missing a large chunk of your internal organs.

6. The Demon Core

The name "Demon Core" sounds like something out of a B horror movie, and it should. The Demon Core was a nuclear device with a rather troublesome tendency to kill researchers. At the Los Alamos labs in the 1940s, the Demon Core was a chunk of subcritical plutonium that was used for research, and on two separate occasions, it went critical, killing scientists. The first was Harry Daghlian, who was working neutron reflection experiments, surrounding the core with neutron reflective bricks. Each one brought the core closer to critical, and when he accidentally dropped a brick on the plutonium mass, it triggered a massive blast of radiation. He pulled it off quickly, but received a fatal dose of radiation, and died 28 days later. The second incident involved Louis Slotin and a group of scientists, who were placing two half-spheres of neutron reflecting beryllium around the plutonium core. The two halves were held apart by a screwdriver wielded by Slotin, but he slipped, and the two closed. The core went supercritical. He pulled apart the halves, thus saving the life of everyone else in the room, but received such a big hit of radiation that he died 9 days later.

5. TGN1412

In the process of researching new drugs, you start by trying them out on small mammals, and slowly working your way up the ladder before eventually reaching us human types. There's a fundamental theory that if it's fine for all the smaller creatures, it's probably going to function in a vaguely similar way for the bigger ones. Sometimes, however, it doesn't. That's what happened with TGN1412, a drug being studied by the company Parexel. A group of study subjects in London were exposed to the drug at a dose 500x lower than was safe in animals. In humans, it caused catastrophic systemic organ failure. Within five minutes, they were in rapidly escalating pain. Basically, their body shut down. Six patients were hospitalized, four died, and one looks like he may be developing cancer. As an ex-drug trial volunteer myself, all I can say is "GAH!"

4. The Tuskegee Syphilis experiment

In the 1930s, syphilis was poorly understood, and many of the treatments toxic in their own right. In 1932, 399 poor black workers with the disease were promised free treatment, but when funding dried up due to the depression the study changed its goal, and the disease was left to run its course so that it could be studied. Now, that's bad enough, but they were trying to find out more about syphilis in order to treat it better, so they had good intentions. But in the 1940s penicillin rocked along, which cured the disease. And the group running the experiment refused to treat the patients with it. They intentionally blocked the patients from learning about penicillin, and prevented them from seeking outside treatment. The experiment ran from 1932 to 1972, at which point, of the original 399 only 74 survived. 28 had died from the disease, 100 from complications associated with it, 40 of their wives were infected, and 19 children were born with congenital syphilis.

3. The Nazi Experiments

There's a reason the Nazi's are such effective villains in so much of our culture. It's very easy to forget some of the shit they did, which was downright torture, in the name of science. The experiments they ran on the people in concentration camps are terrifying and disturbing. Prisoners were dunked in ice water for hours, to see how long downed pilots would survive in the North Atlantic. Decompression chambers were used to test the effects of high altitude, usually followed by live brain dissections to see what happened; they were forced to drink salt water as their only source of fluids; war wounds were inflicted and deliberately infected in order to test new treatments; and TB was brought into the population. These people died under horrific circumstances. Yet these are the only clinical information we have about certain conditions. The hypothermia data in particular is far beyond any other study that could be attempted, which puts researchers in a dilemma. Is it ethical to use data gathered by such disgusting means in order to work on treatments that may save lives?

2. Mengele's twins

As bad as the tales of most Nazi research are, Mengele's experiments were particularly twisted. He worked primarily on young twins, as he was obsessed with unlocking their secrets to increase the birth rate of the "master race". In no particular order, and always without anesthetic , he scraped bone shavings out of gaping holes in peoples legs, combined a pair of twins to create a conjoined body; injected dye or chemicals into their eyes to change the color; drew large amounts of blood; transfused large amounts of blood between twins; spinal taps and injections; one twin would be infected with a disease and the other not; organ removal; castration; amputation; some even allege sex change and incestuous impregnation operations. Some 3000 twins passed through his hands, and only approximately 26 survived. The "angel of death" indeed. After the war, he vanished to South America, where he lived out the rest of his life in remorseless hiding, to die from accidental drowning at the age of 68.

1. Unit 731

While the Nazis were doing their horrific work in Germany, the Japanese outdid them in mainland Asia, undertaking a regime of ruthless experimentation the likes of which are too disturbing to imagine. Everyone knows about Nazi experimentation, but the story of Unit 731 is far less known, and all the more horrific for it. Unit 731 was a research base in Northeast China, and the home of more than 10,000 deaths by experiment. The patients were vivisected without anesthesia after infection with diseases; pregnant women were vivisected and the fetus removed; limbs amputated to study blood loss; said limbs re-attached to the opposite side of the body; extremities were frozen by repeated immersion in water while left in icy conditions, then amputated or thawed to study gangrene; prisoners had their stomachs removed, and their esophagus attached to their intestine directly; live humans were used to test grenades at various ranges and positions; flamethrowers; chemical and biological agents including plague, cholera, smallpox, botulism, syphilis and gonorrhea; being hung upside down until they choked to death; air injected into their arteries to cause embolism; horse urine injected in their kidneys; deprived of food and water till death; placed in high pressure chambers till death; being exposed to extreme cold; burned to see how well they could survive different degrees of burns; spun until death on a centrifuge; animal blood injections; lethal radiation doses; injected with sea water to see if it could be substituted for saline; and buried alive. A laundry list of human atrocities.

While many of the Nazi doctors were at least brought to justice for their crimes, Unit 731 merely disbanded and General MacArthur gave immunity to its doctors in exchange for information on biological warfare, and the majority got off scott free. However, Russia brought war crimes proceedings against a number of the perpetrators, and sentenced them to hard labor in Siberia. I can't help but think they got off light.